Amphiphilic block copolymers

ABSTRACT

The invention relates to novel crosslinkable copolymers of formula 
                         
wherein the variables are as defined in the claims. The copolymers of the invention are especially useful for the manufacture of biomedical moldings, for example ophthalmic moldings such as in particular contact lenses.

This application is a continuation of application Ser. No. 12/321,442filed Jan. 21, 2009 now, U.S. Pat. No. 7,956,135; which is a divisionalapplication of application Ser. No. 09/525,158, now U.S. Pat. No.7,521,519, filed Mar. 14, 2000; which claims the benefit under 35 USC§119(e) of the U.S. provisional patent application Ser. No. 60/183,047,which was converted to a provisional application by petition fromnon-provisional application Ser. No. 09/280,510, filed Mar. 30, 1999.

The present invention relates to novel crosslinkable copolymers, to aprocess for the preparation thereof and to the use thereof for themanufacture of moldings, especially ophthalmic moldings.

U.S. Pat. Nos. 5,760,100 or 5,807,944 disclose crosslinkable amphiphilicblock copolymers comprising a hydrophobic middle block to which arelinked two or more hydrophilic blocks. While the materials disclosedtherein have proven to be very effective as bulk material for themanufacture of biomedical articles, in particular ophthalmic moldings,their surface properties, in particular the wettability characteristics,are in general not sufficient to use them as a biomedical device withoutpreviously applying a suitable coating on their surface.

Therefore, there is a need to provide polymeric materials which may beused for the manufacture of biomedical articles such as ophthalmicmoldings per se without a subsequent surface modification. Surprisingly,it now has been found that articles, particularly biomedical devicessuch as contact lenses, with an improved wettability may be obtainedfrom novel amphiphilic block copolymers comprising a hydrophobic segmentto which are covalently attached moieties comprising a crosslinkableethylenically unsaturated group as well as surface-modifying hydrophilicsegments.

The present invention therefore relates to an amphiphilic blockcopolymer of formula

wherein A is a hydrophobic polysiloxane or perfluoroalkyl polyethersegment;B is a surface-modifying hydrophilic segment having a weight averagemolecular weight of ≧100 that is devoid of a crosslinkable group;Q is a moiety comprising at least one crosslinkable ethylenicallyunsaturated group;(alk) is C₂-C₂₀-alkylene which is unsubstituted or substituted byhydroxy;L₁, L₂ and L₃ are each independently of the other a linking group;p1 and q1 are each independently of the other an integer from 1 to 12;and eithert is 0 and p and q are each independently of the other an integer from 1to 25; ort is an integer from 1 to 8 and p and q are each 0.

In case that t is 0, p and q are each independently of the otherpreferably an integer from 2 to 20, more preferably 2 to 15 and inparticular 2 to 10. In case that p and q are each 0, t is preferably aninteger from 1 to 6, more preferably 1 to 4 and in particular 2. p1 ispreferably an integer from 1 to 6, more preferably 1 to 4 and inparticular 1 or 2. q1 is preferably an integer from 1 to 10, morepreferably 1 to 8, and in particular 1 to 4.

One group of suitable block copolymers of the invention conforms to theformula

wherein A, B, L₁, L₂, L₃, Q, (alk), p1 and q1 are each as defined above.

Another group of suitable block copolymers of the invention conforms toformula

wherein A, B, L₁, L₂ and Q are each as defined above, and p and q areeach independently of the other an integer from 1 to 25, preferably 2 to20, more preferably 2 to 15 and in particular 2 to 10.

In one embodiment of the invention A is a polysiloxane segment offormula

wherein (alk′) is alkylene having 1 to 20 carbon atoms which may beinterrupted by —O—;x is 0 or 1;80 to 100% of the radicals R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄,independently of one another, are C₁-C₈-alkyl, and 0-20% of the radicalsR₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄, independently of one another, areunsubstituted or C₁-C₄ alkyl- or C₁-C₄-alkoxy-substituted phenyl,fluoro(C₁-C₁₈-alkyl) or cyano(C₁-C₁₂-alkyl),s₁ is an integer from 5 to 700;s₂ is the sum of (p+q+t−2) if x is 0, and is the sum of (p+q+t) if x is1; wherein p, q and t are as defined above, andthe sum (s₁+s₂) is from 5 to 700.

In a preferred meaning of the polysiloxanes of formula (2), the sum(s₁+s₂) is an integer from 10 to 500, more preferably 10 to 300, evenmore preferably 20 to 150 and in particular preferably 50 to 140.

(alk′) is preferably C₂-C₈-alkylene, which may be interrupted by —O— andmore preferably C₂-C₆-alkylene which may be interrupted by —O—. Examplesof particular preferred radicals (alk′) are linear or branched C₂-C₆alkylene or a radical —(CH₂)₁₋₃—O—(CH₂)₁₋₃—, especially C₂-C₄-alkyleneor a radical —(CH₂)₂₋₃—O—(CH₂)₂₋₃—.

Preferably the radicals R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄ are eachindependently of one another C₁-C₆-alkyl, more preferably eachC₁-C₄-alkyl, more preferably each C₁-C₂-alkyl and in particular eachmethyl.

One embodiment of suitable polysiloxane hydrophobic blocks (A)emcompasses a radical of the above formula (2), wherein x is 0, s2 is 0,s1 is an integer from 5 to 700, preferably 10 to 500, more preferably 10to 300, even more preferably 20 to 150 and in particular preferably 50to 140, R₁, R₁′, R₁″, R₂, R₂′, R₂″ and R₃ are each independently of oneanother C₁-C₆-alkyl, and for (alk′) the above given meanings andpreferences apply. In this case, either t in formula (1) is 0 and p andq are each 1, or, preferably, p and q are each 0 and t is 2.

Another embodiment of suitable polysiloxane hydrophobic blocks (A)encompasses a radical of the above formula (2), wherein x is 0, s₂ isthe sum of (p+q+t−2), and for R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃, (alk′), p,q and t the above-given meanings and preferences each apply.

Still another embodiment of suitable polysiloxane hydrophobic blocks (A)encompasses a radical of the above formula (2), wherein x is 1, s₂ isthe sum of (p+q+t), and for R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃, R₄, p, q andt the above-given meanings and preferences each apply.

In another embodiment of the invention, A is a perfluoroalkyl polyethersegment of formula-(E)_(k)-Z—CF₂—(OCF₂)_(y1)—(OCF₂CF₂)_(y2)—OCF₂—Z-(E)_(k)-  (3),in which y1+y2 is a number in the range from 10 to 100; each Z,independently of the other, is a divalent radical having up to 12 carbonatoms or a bond; each E, independently of the others, is alkoxy, e.g.—(OCH₂CH₂)_(r)—, where r has a value of from 0 to 2 as a statisticalaverage, and where the link —Z-E- represents the sequence—Z—(OCH₂CH₂)_(r)—; and k is 0 or 1;

Z is preferably a bond, C₁-C₈-alkylene or —CONH-phenylene, in which the—CO— moiety is linked to a CF₂ group. Z is particularly preferablyC₁-C₄-alkylene, in particular methylene.

The perfluoroalkoxy units OCF₂ and OCF₂CF₂ having the indices y1 and y2in Formula (3) can have a random distribution. The sum of the indicesy1+y2 is preferably a number in the range from 10 to 50, particularlypreferably from 10 to 30. The ratio y1:y2 is preferably in the rangefrom 0.5 to 1.5, in particular in the range from 0.8 to 1.2.

In one embodiment of the invention, the segment A may comprise one ofthe polymers illustrated above. According to another embodiment, thepolymer in segment A may comprise more than one kind of polymers asillustrated above, e.g., may comprise polysiloxane subsegments offormula (2) and perfluoroalkylene polyether units of formula (3).Preferably, segment A is a polysiloxane of formula (2).

Segments A of the prepolymers of the invention have a mean molecularweight of for example in the range from about 1,000 to about 50,000,preferably in the range from about 1,500 to about 30000 and particularlypreferably in the range from about 2,000 to about 20,000.

L₁, L₂ and L₃ are each independently of the other, for example, abivalent linking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e),wherein X₁ and X₂ are each independently of the other a group —O—, —S—or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀ is linear or branchedC₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl- orC₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₈-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene.

The linking groups L₁ and L₂ of formulae (4a)-(4e) are to be understoodthat the left bond is in each case directed to A or (alk) and the rightbond is directed to Q or B. The linking group L₃ of formulae (4a)-(4e)is to be understood that the left bond is directed to A and the rightbond is directed to (alk).

If X₁ or X₂ is a group —NR₀—, R₀ is preferably methyl, ethyl or inparticular hydrogen.

In formulae (4a)-(4e) X₁ and X₂ are each independently of the otherpreferably a group —O— or —NR₀— and more preferably —O— or —NH—.

R₁₀ as alkylene in formulae (4a) and (4b) is preferably linear orbranched C₁-C₁₂-alkylene, more preferably C₁-C₆-alkylene and mostpreferably C₁-C₄-alkylene.

R₁₀ as alkylene in formula (4a) is preferably a linear or branchedC₃-C₁₄alkylene radical, more preferably a linear or branchedC₄-C₁₂alkylene radical and most preferably a linear or branchedC₆-C₁₀alkylene radical. Some preferred alkylene radicals are1,4-butylene, 2,2-dimethyl-1,4-butylene, 1,5-pentylene,2,2-dimethyl-1,5-pentylene, 1,6-hexylene, 2,2,3- or2,2,4-trimethyl-1,5-pentylene, 2,2-dimethyl-1,6-hexylene, 2,2,3- or2,2,4- or 2,2,5-trimethyl-1,6-hexylene, 2,2-dimethyl-1,7-heptylene,2,2,3- or 2,2,4- or 2,2,5- or 2,2,6-trimethyl-1,7-heptylene,1,8-octylene, 2,2-dimethyl-1,8-octylene and 2,2,3- or 2,2,4- or 2,2,5-or 2,2,6- or 2,2,7-trimethyl-1,8-octylene.

When R₁₀ is arylene, it is, for example, naphthylene or especiallyphenylene, each of which may be substituted, for example, by C₁-C₄-alkylor by C₁-C₄-alkoxy. Preferably, R₁₀ as arylene is 1,3- or 1,4-phenylenethat is unsubstituted or substituted by C₁-C₄-alkyl or by C₁-C₄-alkoxyin the ortho-position to at least one linkage site. Examples ofsubstituted arylene are 1-methyl-2,4-phenylene,1,5-dimethyl-2,4-phenylene, 1-methoxy-2,4-phenylene and1-methyl-2,7-naphthylene.

R₁₀ as aralkylene is preferably naphthylalkylene and most preferablyphenylalkylene. The alkylene group in aralkylene contains preferablyfrom 1 to 12, more preferably from 1 to 6 and most preferably from 1 to4 carbon atoms. Most preferably, the alkylene group in aralkylene ismethylene or ethylene. Some examples are 1,3- or 1,4-benzylene,naphth-2-yl-7-methylene, 6-methyl-1,3- or -1,4-benzylene and6-methoxy-1,3- or -1,4-benzylene.

When R₁₀ is cycloalkylene, it is preferably C₅-C₆cycloalkylene and mostpreferably cyclo-hexylene that is unsubstituted or substituted bymethyl. Some examples are 1,3-cyclobutylene, 1,3-cyclopentylene, 1,3- or1,4-cyclohexylene, 1,3- or 1,4-cycloheptylene, 1,3- or 1,4- or1,5-cyclooctylene, 4-methyl-1,3-cyclopentylene,4-methyl-1,3-cyclohexylene, 4,4-dimethyl-1,3-cyclohexylene, 3-methyl- or3,3-dimethyl-1,4-cyclohexylene, 3,5-dimethyl-1,3-cyclohexylene and2,4-dimethyl-1,4-cyclohexylene.

When R₁₀ is cycloalkylene-alkylene, it is preferablycyclopentylene-C₁-C₄-alkylene and especiallycyclohexylene-C₁-C₄-alkylene, each unsubstituted or mono- orpoly-substituted by C₁-C₄-alkyl, especially methyl. More preferably, thegroup cycloalkylene-alkylene is cyclohexylene-ethylene and, mostpreferably, cyclohexylene-methylene, each unsubstituted or substitutedin the cyclohexylene radical by from 1 to 3 methyl groups. Some examplesare cyclopent-1-yl-3-methylene, 3-methyl-cyclopent-1-yl-3-methylene,3,4-dimethyl-cyclopent-1-yl-3-methylene,3,4,4-trimethyl-cyclopent-1-yl-3-methylene, cyclohex-1-yl-3- or-4-methylene, 3- or 4- or 5-methyl-cyclohex-1-yl-3- or -4-methylene,3,4- or 3,5-dimethyl-cyclohex-1-yl-3- or -4-methylene and 3,4,5- or3,4,4- or 3,5,5-trimethyl-cyclohex-1-yl-3- or -4-methylene.

When R₁₀ is alkylene-cycloalkylene-alkylene, it is preferablyC₁-C₄-alkylene-cyclopentylene-C₁-C₄-alkylene and especiallyC₁-C₄-alkylene-cyclohexylene-C₁-C₄-alkylene, each unsubstituted or mono-or poly-substituted by C₁-C₄-alkyl, especially methyl. More preferably,the group alkylene-cycloalkylene-alkylene isethylene-cyclohexylene-ethylene and, most preferably, ismethylene-cyclohexylene-methylene, each unsubstituted or substituted inthe cyclohexylene radical by from 1 to 3 methyl groups. Some examplesare cyclopentane-1,3-dimethylene, 3-methyl-cyclopentane-1,3-dimethylene,3,4-dimethyl-cyclopentane-1,3-dimethylene,3,4,4-trimethyl-cyclopentane-1,3-dimethylene, cyclohexane-1,3- or-1,4-dimethylene, 3- or 4- or 5-methyl-cyclohexane-1,3- or-1,4-dimethylene, 3,4- or 3,5-dimethyl-cyclohexane-1,3- or-1,4-dimethylene, 3,4,5- or 3,4,4- or 3,5,5-trimethyl-cyclohexane-1,3-or -1,4-dimethylene.

R₁₀ as C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene is preferablyC₅-C₆-cycloalkylene-methylene-C₅-C₆-cycloalkylene orphenylene-methylene-phenylene, each of which may be unsubstituted orsubstituted in the cycloalkyl or phenyl ring by one or more methylgroups.

The radical R₁₀ in formula (4a) has a symmetrical or, preferably, anasymmetrical structure.

A preferred group of linking groups L₁ or L₂ comprises those of formula(4a), wherein R₁₀ is linear or branched C₆-C₁₀alkylene;cyclohexylene-methylene or cyclohexylene-methylene-cyclo-hexylene eachunsubstituted or substituted in the cyclohexyl moiety by from 1 to 3methyl groups; or phenylene or phenylene-methylene-phenylene eachunsubstituted or substituted in the phenyl moiety by methyl.

The bivalent radical R₁₀ in formula (4a) is derived preferably from adiisocyanate and most preferably from a diisocyanate selected from thegroup isophorone diisocyanate (IPDI), toluoylene-2,4-diisocyanate (TDI),4,4′-methylenebis(cyclohexyl isocyanate),1,6-diisocyanato-2,2,4-trimethyl-n-hexane (TMDI), methylenebis(phenylisocyanate), methylenebis(cyclohexyl-4-isocyanate) and hexamethylenediisocyanate (HMDI).

Another preferred group of linking groups L₁ or L₂ comprises those offormula (4b), wherein R₁₀ is C₁-C₆-alkylene or 1,3- or 1,4-phenylene.

Further preferred linking groups L₁ or L₂ comprise —O(O)C—, —C(O)O—,—HNC(O)—, —C(O)NH—, —OC(O)O— and HNC(O)NH—.

A preferred group of linking groups L₃ comprises those of formula (4b)or (4c), wherein the above meanings and preferences apply.

Suitable hydrophilic segments B are for example:

(i) non-ionic segments, for example a polyoxyalkylene, polysaccharide,polypeptide, poly(vinylpyrrolidone), polyhydroxyalkylacrylate or-methacrylate, polyacyl alkylene imine, polyacryl amide, polyvinylalcohol, polyvinyl ether or polyol;

(ii) polyionic segments, for example a polycationic segment such as apolyallylammonium, polyethyleneimine, polyvinylbenzyltrimethylammonium,polyaniline, sulfonated polyaniline, polypyrrole or polypyridiniumsegment, or a polyanionic segment such as a polyacrylic orpolymethacrylic acid, a polythiophene-acetic acid, a polystyrenesulfonicacid, or a zwitterionic segment. Polyionic segments in each caseencompass the free amine, imine or acid or a suitable salt thereof.

Some examples of preferred hydrophilic segments B are a polyoxyalkylene,such as a polyethylene glycol or polypropylene glycol or a blockcopolymer thereof, a poly(vinylpyrrolidone), poly(hydroxyethylacrylate),poly(hydroxyethylmethacrylate), polyacrylamide,poly(N,N-dimethylacrylamide), polyacrylic or polymethacrylic acid, apolyacyl alkylene imine or a copolymeric mixture of two or more of theabove-mentioned polymers.

B as a polyoxyalkylene radical may correspond, for example, to formulaR₅—[(O—CHR₇—CHR₆)_(b)—(O—CH₂—CH₂)_(a)]—(O-(alk″))_(c)-  (5)wherein R₅ is hydrogen, C₁-C₂₄-alkyl, C₁-C₂₄-alkanoyl or a radical-(alk″)-NH₂, one of the radicals R₆ and R₇ is hydrogen and the other ismethyl, (alk″) is C₁-C₆-alkylene, c is the number 0 or 1, and each of aand b independently of the other is a number from 0 to 100, the sum of(a+b) being from 2 to 100.

In formula (5), R₅ is preferably hydrogen, C₁-C₄-alkyl orC₁-C₄-alkanoyl, more preferably hydrogen or C₁-C₂-alkyl and inparticular hydrogen. (alk″) is preferably C₂-C₄-alkylene and inparticular 1,2-ethylene or 1,2- or 1,3-propylene. The variable cpreferably is an integer of 0. Each of a and b independently of theothers is preferably a number from 0 to 80, the sum of (a+b) being from3 to 80. Most preferably, each of a and b independently of the others isa number from 0 to 50, the sum of (a+b) being from 4 to 50 andespecially from 8 to 50. A preferred embodiment relates topolyoxyalkylene segments of formula (5) wherein b and c are each 0, R₅is hydrogen, C₁-C₄-alkyl or C₁-C₄-alkanoyl, and for the variable a theabove-mentioned meanings and preferences apply.

B as a polyacyl alkylene imine may correspond, for example, to a segmentof formula

wherein R₈ is hydrogen; C₁-C₁₂-alkyl unsubstituted or substituted byhydroxy or fluoro and/or uninterrupted or interrupted by oxygen;C₅-C₈-cycloalkyl; phenyl; or benzyl, R₉ is, for example, C₁-C₁₂-alkyl,benzyl, C₂-C₄-alkanoyl, benzoyl or phenyl, preferably C₁-C₆-alkyl,acetyl or benzyl and in particular C₁-C₄-alkyl, and z is an integer from2 to 150.

R₈ is preferably C₁-C₈-alkyl which is unsubstituted or substituted byhydroxy or fluorine and/or is uninterrupted or interrupted by —O—; or isC₃-C₈-alkenyl. R₈ is more preferably C₁-C₄-alkyl, hydroxy-C₁-C₄-alkyl ortrifluoromethyl and most preferably methyl. z is preferably an integerfrom 4 to 100, more preferably 4 to 50 and especially 5 to 20.

The mean weight average molecular weight of the hydrophilic blocks B mayvary within wide limits. A preferred embodiment of the invention relatesto prepolymers, particularly to prepolymers for ophthalmic uses, whereinsegments B have a mean molecular weight in the range from about 200 toabout 10,000, preferably in the range from about 350 to about 5000 andparticularly preferably in the range from about 500 to about 1,500.

The hydrophilic blocks B are preferably linked to A or (alk) by alinking group L₂ of formula (4a).

Q is, for example, a crosslinkable or polymerizable group Q₁ or ahydrophilic segment comprising a crosslinkable or polymerizable groupsuch as Q₁.

Q as a group Q₁ is, for example, a radical of formula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which may be further substituted, and w is the number0 or 1.

Suitable substituents on the olefinic C₂-C₂₄ radical R₁₁ are, forexample, C₁-C₄alkoxy, halogen, phenyl or carboxy. R₁₁ is, for example, aradical of formula

wherein I is the number 0 or 1, R₁₂ is hydrogen, C₁-C₄-alkyl or halogen,each of R₁₃ and R₁₄ independently of the other is hydrogen, C₁-C₄-alkyl,phenyl, carboxy or halogen, and R₁₅ is linear or branchedC₁-C₁₂-alkylene or unsubstituted or C₁-C₄-alkyl- orC₁-C₄-alkoxy-substituted phenylene or C₇-C₁₂-aralkylene.

When R₁₅ is a phenylene radical, it is, for example, unsubstituted ormethyl- or methoxy-substituted 1,2-, 1,3- or 1,4-phenylene. Preferably,R₁₅ as a phenylene radical is 1,3- or 1,4-phenylene.

When R₁₅ is an aralkylene radical, it is, for example, unsubstituted ormethyl- or methoxy-substituted benzylene, wherein the methylene group isbonded to the amine nitrogen in each case. Preferably, Z′ as anaralkylene radical is the 1,3- or 1,4-phenylenemethylene radical,wherein the methylene group is bonded to the amine nitrogen —NH— in eachcase.

R₁₅ is preferably unsubstituted or methyl- or methoxy-substitutedphenylene or phenylene-methylene or C₁-C₁₂alkylene, more preferably 1,3-or 1,4-phenylene or C₁-C₆alkylene, especially C₁-C₂alkylene and mostpreferably methylene.

I is the number 1 or, preferably, the number 0. R₁₂ is preferablyhydrogen, methyl or chlorine and most preferably hydrogen or methyl.

Each of R₁₃ and R₁₄ independently of the other is preferably hydrogen,carboxy, chlorine, methyl or phenyl. In a preferred embodiment of theinvention, R₁₃ is hydrogen, chlorine, methyl or phenyl and R₁₄ ishydrogen or carboxy. Most preferably, R₁₃ and R₁₄ are each hydrogen.

Examples of suitable radicals R₁₁ are vinyl, 1-methylvinyl, 2-propenyl,allyl, 2-butenyl, o-, m- or p-vinylphenyl, styryl, 2-carboxyvinyl,2-chloro-2-carboxyvinyl, 1,2-dichloro-2-carboxyvinyl,1,2-dimethyl-2-carboxyvinyl and 2-methyl-2-carboxyvinyl.

Especially preferred radicals R₁₁ correspond to formula (8) wherein I is0, R₁₂ is hydrogen or methyl, R₁₃ is hydrogen, methyl, chlorine orphenyl, in particular hydrogen, and R₁₄ is carboxy or particularlyhydrogen.

Other especially preferred radicals R₁₁ correspond to the above formula(8) wherein I is 1, R₁₅ is 1,3- or 1,4-phenylene or C₁-C₆-alkylene,especially C₁-C₂-alkylene, R₁₂ is hydrogen or methyl and R₁₃ and R₁₄ areeach hydrogen.

(Alk) is preferably C₁-C₄-alkylene, especially methylene or1,1-dimethylmethylene.

The crosslinkable or polymerizable group Q₁ is preferably linked to A or(alk) by a linking group L₁ of formula (4a), (4c) or (4e).

One group of suitable radicals L₁-Q₁ are those wherein L₁ is a radicalof formula (4c) wherein X₁ is —NH— or in particular —O—, Q₁ correspondsto a radical of the above formula (7) wherein w is 0, and for R₁₁ theabove given meanings and preferences apply.

A second group of suitable radicals L₁-Q₁ are those wherein L₁ is aradical of formula (4c) wherein X₁ is —NH— or in particular —O—, Q₁corresponds to a radical of the above formula (7) wherein w is 1, andfor R₁₁ the above given meanings and preferences apply.

Still another group of suitable radicals L₁-Q₁ are those wherein L₁ is aradical of formula (4e) wherein X₁ is —NH— or in particular —O—, X₂ is—NH—, Q₁ corresponds to a radical of the above formula (7) wherein w is1, and for R₁₁ the above given meanings and preferences apply.

Especially preferred radicals -L₁-Q₁ correspond to formula

wherein X₁ is —O— or —NH—, in particular —O—.

Q as a hydrophilic segment comprising a crosslinkable or polymerizableC—C double bond group is, for example a polyoxyalkylene, such as apolyethylene glycol or polypropylene glycol or a block copolymerthereof, a poly(vinylpyrrolidone), poly(hydroxyethylacrylate),poly(hydroxy-ethylmethacrylate), polyacrylamide,poly(N,N-dimethylacrylamide), polyacrylic or polymethacrylic acid, apolyacyl alkylene imine or a copolymeric mixture of two or more of theabove-mentioned polymers which in each case comprises one or more,preferably 1, ethylenically unsaturated bond and has a weight averagemolecular weight of, for example, ≧100.

C—C double bond containing hydrophilic segments Q advantageously have amean molecular weight in the range from about 200 to about 10,000,preferably in the range from about 350 to about 5000 and particularlypreferably in the range from about 500 to about 1,500.

Examples of suitable C—C double bond containing hydrophilic segments Qare a radical of formula

wherein for L₁′ and Q₂ each the meanings and preferences given above forL₁ and Q₁ apply, Q₃ is C₃-C₁₂-alkenyl or a radical —(CH₂)₁₋₄—O—R₁₆wherein R₁₆ is acryloyl, methacryloyl or a group—C(O)—NH—(CH₂)₂₋₄—O—C(O)—C(R₁₇)═CH₂ and R₁₇ is hydrogen or methyl,

-   -   Q₄ is a radical of formula

wherein X₃ is —O— or —NR, R is hydrogen or C₁-C₄-alkyl, X₄ is a group—C(O)—O—, —O—C(O)—NH— or —NH—C(O)—O—, (Alk′) is C₁-C₈-alkylene, e is aninteger of 0 or 1, and R₁₈ is C₁-C₁₂-alkylene, phenylene orC₇-C₁₂-phenylenealkylene, and for R₆, R₇, R₈, R₉, (alk″), a, b, c and zeach the above-given meanings and preferences apply.

Q₃ in formula (6a) is preferably a radical —(CH₂)₂₋₄—O—R₁₆ wherein R₁₆is acryloyl, methacryloyl or a group —C(O)—NH—(CH₂)₂—O—C(O)—C(R₁₇)═CH₂,and R₁₇ is hydrogen or methyl.

Preferred meanings of the variables contained in formulae (9a)-(9d) are:

R is preferably methyl, ethyl or, in particular, hydrogen. X₃ in formula(9a) is preferably —O— or —NH—. X₃ in formula (9b) is preferably —NH—.X₃ in formula (9c) is preferably —O—. X₄ is preferably the radical—NH—C(O)—O—. R₁₈ is preferably C₁-C₆-alkylene or benzyl and morepreferably C₁-C₄-alkylene or benzyl, and most preferably methyl, ethylor benzyl. (Alk′) is preferably C₂-C₆-alkylene and in particularC₂-C₄-alkylene. e is preferably the number 1.

Some examples of suitable radicals Q₄ are o-, m- or p-vinylbenzyl,allyl, acryloyl-C₁-C₄-alkyl, in particular acryloylethyl,methacryloyl-C₁-C₄-alkyl, in particular methacryloylethyl,acrylamido-C₁-C₄-alkyl, in particular acrylamidoethyl,methacrylamido-C₁-C₄-alkyl, in particular methacrylamidoethyl,vinyloxycarbonyl-C₁-C₄-alkyl, in particular vinyloxycarbonylmethyl orvinyloxycarbonylethyl, and vinylcarbonyl.

Q as a hydrophilic block comprising an ethylenically unsaturated groupis preferably linked to A or (alk) by a linking group L₁ of formula(4a).

(alk) is preferably C₂-C₁₂-alkylene, more preferably C₃-C₁₀-alkylene andmost preferably C₄-C₈-alkylene, which is in each case unsubstituted orsubstituted by hydroxy. (alk) is preferably linked to A by a linkinggroup L₃ of formula (4a) or (4c).

The amphiphilic block copolymers of the invention wherein t is 0 and L₁and L₂ are each a linking group of formula (4a) or (4b) may be prepared,for example, by reacting in any order a compound of formulaA-(X₁H)_(p+q)  (10),about (p+q) molar equivalents of a compound of formulaY—R₁₀—Y  (11)about p molar equivalents of a compound of formulaQ-X₂H  (12),and about q molar equivalents of a compound of formulaB—X₂′H  (13),each, wherein Y is a group —N═C═O or carboxy or a suitable derivativethereof, for example a group —C(O)OH, —C(O)OR₁₉ or —C(O)—OHal whereinR₁₉ is, for example, C₁-C₄-alkyl, phenyl or benzyl and Hal is halogen,in particular bromine or chlorine, X₂′ independently has the meaning ofX₂, and A, B, X₁, X₂, p and q are as defined above.

For example, the compounds of formulae (12) and (13) may be firstreacted with about one molar equivalent of a compound of formula (11)each, and the intermediates obtained are then reacted with the compoundof formula (10). Another synthetic route comprises first reacting acompound of formula (10) with a compound of formula (11), and theintermediate obtained is then reacted with a mixture of the compounds offormulae (12) and (13).

Where the compound of formula (11) is a carboxylic acid or a derivativethereof, e.g. a carboxylic acid halide, the reaction thereof with thecomponents of formulae (10), (12) and (13), respectively, can be carriedout under the conditions that are customary for ester, thioester, oramide formation, for example at temperatures of, for example, from −40to 80° C., preferably from 0 to 50° C. and most preferably from 0 to 25°C., in a dipolar aprotic solvent, e.g. tetrahydrofuran, dioxane, DMSO oran aprotic solvent as mentioned below, or in a mixture of water and oneof the mentioned solvents, in the presence of a base, e.g. an alkalimetal hydroxide, and, where applicable, in the presence of a stabiliser.Suitable stabilisers are, for example, 2,6-dialkylphenols, hydroquinonederivatives, e.g. hydroquinone or hydroquinone monoalkyl ethers, orN-oxides, e.g. 4-hydroxy-2,2,6,6-tetramethyl-piperidin-1-yl. Thereaction times may vary within wide limits, a period of, for example,from 30 minutes to 12 hours, preferably from 1 to 6 hours and especiallyfrom 2 to 3 hours, generally having been found practicable.

Where the compound of formula (11) is an isocyanate, the reactionthereof with the components of formulae (10), (12) and (13),respectively, can be carried out under the conditions that are customaryfor the formation of urethanes or ureas. In case of urethane formationit is advantageously to perform the reaction in an inert solvent. Aminesof the formula (10), (12) and (13) may be reacted with the diisocyanateof formula (11) also in an aqueous medium. It is especially advantageousto use diisocyanates having isocyanate groups of differing reactivitysince the formation of isomers and diadducts can thereby besubstantially suppressed. The differing reactivity can be brought about,for example, by steric hindrance.

Suitable inert solvents for the reaction of the compounds of formulae(10), (12) or (13) with a compound of formula (11) are aprotic,preferably polar, solvents, for example hydrocarbons (petroleum ether,methylcyclohexane, benzene, toluene, xylene), halogenated hydrocarbons(chloroform, methylene chloride, trichloroethane, tetrachloroethane,chlorobenzene), ethers (diethyl ether, dibutyl ether, ethylene glycoldimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran,dioxane), ketones (acetone, dibutyl ketone, methyl ethyl ketone, methylisobutyl ketone), carboxylic acid esters and lactones (ethyl acetate,butyrolactone, valerolactone), alkylated carboxylic acid amides(N,N-dimethylacetamide, N-methylpyrrolidone), nitriles (acetonitrile),sulfones and sulfoxides (dimethyl sulfoxide, tetramethylenesulfone).Polar solvents are preferably used. The reaction temperature may be, forexample, from −40 to 200° C. When catalysts are used, the temperaturesmay advantageously be in the range of from 0 to 50° C., preferably atroom temperature. Suitable catalysts are, for example, metal salts, suchas ferric chloride or alkali metal salts of carboxylic acids, tertiaryamines, for example (C₁-C₆alkyl)₃N (triethylamine, tri-n-butylamine),N-methylpyrrolidine, N-methylmorpholine, N,N-dimethylpiperidine,pyridine and 1,4-diaza-bicyclooctane. Tin salts have been found to beespecially effective, especially alkyltin salts of carboxylic acids, forexample dibutyltin dilaurate and tin dioctoate. The isolation andpurification of the compounds prepared is carried out according to knownmethods, for example by means of extraction, crystallisation,recrystallisation or chromatographic purification methods.

The amphiphilic block copolymers of the invention wherein t is 0 and L₁and L₂ are each a linking group of formulae (4c), (4d) or (4e) may beprepared, for example, by reacting a compound of the formulaA-(Y)_(p+q)  (10a)with about p molar equivalents of a compound of the above formula (12)and q molar equivalents of a compound of formula (13), or by reacting acompound of the above formula (10) with about p molar equivalents of acompound of formulaQ-Y  (12a)and about q molar equivalents of a compound of formulaB—Y  (13a),wherein A, B, Q, Y, p and q each have the above-mentioned meaning.

The reaction of the components of formulae (10a) and (12) and (13) or(10) and (12a) and (13a), respectively, can be carried out under theconditions that are customary for ester, thioester, amide, urethane orurea formation, for example as outlined above.

The amphiphilic block copolymers of the invention wherein p and q areeach 0 and L₁ and L₂ are each a linking group of formula (4a), (4b),(4c) or (4e) may be prepared, for example, by reacting a compound offormula

with(i) about p1 molar equivalents of a compound of formula (12a) or thereaction product of a compound of formula (11) and (12); and(ii) about q1 molar equivalents of a compound of formula (13a) or thereaction product of a compound of formula (11) and (13),wherein A, L₃, X₁, (alk), p1 and q1 are each as defined above.

The reactions can be carried out under the conditions that are customaryfor ester, thioester, amide, urethane or urea formation, for example asoutlined above. A linking group L₁ or L₂ of formula (4d) in the aboveamphiphilic block copolymers may be prepared, for example, by reacting acompound which is analogous to the compound of formula (14) but containsa carboxy group or an above-mentioned derivative thereof with a compoundof formula (12) or (13).

The compounds of formula (14) are known or may be prepared according toprocesses known in the art, for example by reacting a compoundA-(X₁H)_(t) with a compound Y₁-(alk)-(X₁′H)_(p1+q1) or

wherein X₁′ independently has the meaning of X₁, Y₁ is carboxy or anabove-mentioned derivative thereof, and X₁, (alk), p1 and q1 each havethe above-mentioned meaning.

The molecular weight of the copolymers of the invention is, within widelimits, not critical. Preferably, however, the prepolymer has a weightaverage molecular weight of from approximately 1400 to 200000,preferably from 2000 to 100000 and more preferably from 2500 to 50000and most preferably from 3000 to 25000.

The amphiphilic block copolymers of formula (1) are crosslinkable, butare uncrosslinked or, at least, substantially uncrosslinked; inaddition, they are stable, that is to say spontaneous crosslinking as aresult of homopolymerization does not take place.

The amphiphilic block copolymers of formula (1) according to theinvention are crosslinkable in a controlled and extremely effectivemanner, especially by photo-crosslinking.

The present invention further relates, therefore, to a polymer that canbe obtained by photo-crosslinking of a amphiphilic block copolymers offormula (1), in the presence or, preferably, in the absence of anadditional vinyl comonomer. These crosslinked polymers arewater-insoluble.

In the photo-crosslinking, a photoinitiator capable of initiatingfree-radical crosslinking is suitably added. Examples thereof will befamiliar to the person skilled in the art, suitable photoinitiators thatmay specifically be mentioned being benzoin methyl ether,1-hydroxycyclohexylphenyl ketone, Darocure 1173 or Irgacure types. Thecrosslinking can then be brought about by actinic radiation, e.g. UVlight, or ionising radiation, e.g. gamma rays or X-rays. The amount ofphotoinitiator may be selected within wide limits, an amount of up to0.05 g/g of polymer and especially of up to 0.01 g/g of polymer havingproved beneficial.

The amphiphilic block copolymers of formula (1) is introduced into thecrosslinking process preferably in pure form, particularly substantiallyfree from undesired constituents, such as, for example, free frommonomeric, oligomeric or polymeric starting compounds used for thepreparation of the copolymer, and/or free from secondary products formedduring the preparation of the copolymer. Said copolymers in pure formare obtained advantageously by previously purifying them in a mannerknown per se, for example by precipitation with a suitable solvent,filtration and washing, extraction in a suitable solvent, dialysis,reverse osmoses (RO) or ultrafiltration, reverse osmoses andultrafiltration being especially preferred.

The preferred purification processes for the copolymers of theinvention, reverse osmoses and ultrafiltration, can be carried out in amanner known per se. It is possible for the ultrafiltration and reverseosmoses to be carried out repeatedly, for example from two to ten times.Alternatively, the ultrafiltration and reverse osmoses can be carriedout continuously until the selected degree of purity is attained. Theselected degree of purity can in principle be as high as desired.

The copolymers of formula (1) may be crosslinked, for example, in formof a solution or a mesophase.

One embodiment of the invention relates to the photo-polymerisation ofthe block copolymers of the invention in solution, preferably in one ormore different organic solvents. Suitable solvents are in principle allsolvents that dissolve the polymers according to the invention and anoptional vinyl comonomer which may be additionally used, e.g. alcohols,such as C₁-C₆-alkanols, e.g. n- or iso-propanol, ethanol or methanol,carboxylic acid amides, such as dimethylformamide, or dimethylsulfoxide, and mixtures of suitable solvents, e.g. mixtures of waterwith an alcohol, e.g. a water/propanol, water/ethanol or awater/methanol mixture.

According to this embodiment of the invention, the photo-crosslinking ispreferably effected from a solution comprising (i) one or moreprepolymers according to the invention which can be obtained as a resultof the preferred purification step, ultrafiltration, (ii) one or moresolvents selected from the group consisting of a C₁-C₆-alkanol, acarboxylic acid amide, dimethyl sulfoxide and water, and optionally(iii) an additional vinyl comonomer. For example, photo-crosslinking ofthe block copolymers is carried out in ethanol or n- or iso-propanol.

The vinyl comonomer that can additionally be used according to theinvention in the photo-crosslinking may be hydrophilic or hydrophobic ormay be a mixture of a hydrophobic and a hydrophilic vinyl monomer.Suitable vinyl monomers include especially those which are customarilyused in the manufacture of contact lenses. The expression “hydrophilicvinyl monomer” is understood to mean a monomer that typically producesas homopolymer a polymer that is water-soluble or capable of absorbingat least 10% by weight water. Analogously, the expression “hydrophobicvinyl monomer” is understood to mean a monomer that typically producesas homopolymer a polymer that is water-insoluble or capable of absorbingless than 10% by weight water.

The proportion of vinyl comonomers, if used, is preferably from 0.5 to80 units per copolymer of formula (1), especially from 1 to 30 units ofvinyl comonomer per copolymer unit of formula (1) and most preferablyfrom 5 to 20 units per copolymer of formula (1).

It is also preferred to use a hydrophobic vinyl comonomer or a mixtureof a hydrophobic vinyl comonomer with a hydrophilic vinyl comonomer, themixture containing at least 50% by weight of a hydrophobic vinylcomonomer. In that manner, the mechanical properties of the polymer canbe improved without the water content being appreciably reduced. Inprinciple, however, both conventional hydrophobic vinyl comonomers andconventional hydrophilic vinyl comonomers are suitable forcopolymerisation with a prepolymer of formula (1).

Suitable hydrophobic vinyl comonomers include, without the followingbeing an exhaustive list, C₁-C₁₈alkyl acrylates and methacrylates,C₃-C₁₈alkylacrylamides and -methacrylamides, acrylonitrile,methacrylonitrile, vinyl-C₁-C₁₈alkanoates, C₂-C₁₈alkenes,C₂-C₁₈haloalkenes, styrene, C₁-C₆alkylstyrene, vinyl alkyl ethers inwhich the alkyl moiety has from 1 to 6 carbon atoms, C₂-C₁₀perfluoroalkyl acrylates and methacrylates or correspondingly partiallyfluorinated acrylates and methacrylates,C₃-C₁₂perfluoroalkyl-ethyl-thiocarbonylaminoethyl acrylates andmethacrylates, acryloxy- and methacryloxy-alkylsiloxanes,N-vinylcarbazole, C₁-C₁₂alkyl esters of maleic acid, fumaric acid,itaconic acid, mesaconic acid and the like. Preferred are, for example,C₁-C₄alkyl esters of vinylically unsaturated carboxylic acids havingfrom 3 to 5 carbon atoms or vinyl esters of carboxylic acids having upto 5 carbon atoms.

Examples of suitable hydrophobic vinyl comonomers include methylacrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate,cyclohexyl acrylate, 2-ethylhexyl acrylate, methyl meth-acrylate, ethylmethacrylate, propyl methacrylate, vinyl acetate, vinyl propionate,vinyl butyrate, vinyl valerate, styrene, chloroprene, vinyl chloride,vinylidene chloride, acrylonitrile, 1-butene, butadiene,methacrylonitrile, vinyltoluene, vinyl ethyl ether,perfluorohexylethylthio-carbonylaminoethyl methacrylate, isobornylmethacrylate, trifluoroethyl methacrylate, hexa-fluoroisopropylmethacrylate, hexafluorobutyl methacrylate,tris-trimethylsilyloxy-silyl-propyl methacrylate,3-methacryloxypropylpentamethyldisiloxane andbis(methacryloxypropyl)-tetramethyldisiloxane.

Suitable hydrophilic vinyl comonomers include, without the followingbeing an exhaustive list, hydroxy-substituted lower alkyl acrylates andmethacrylates, acrylamide, methacrylamide, lower alkylacrylamide and-methacrylamide, ethoxylated acrylates and methacrylates,hydroxy-substituted lower alkylacrylamides and methacrylamides,hydroxy-substituted lower alkyl vinyl ethers, sodium ethylenesulfonate,sodium styrenesulfonate, 2-acrylamido-2-methylpropanesulfonic acid,N-vinylpyrrole, N-vinylsuccinimide, N-vinylpyrrolidone, 2- or4-vinylpyridine, acrylic acid, methacrylic acid, amino- (the term“amino” also including quaternary ammonium), mono-lower alkylamino- ordi-lower alkylamino-lower alkyl acrylates and methacrylates, allylalcohol and the like. Preferred are, for example, hydroxy-substitutedC₂-C₄alkyl (meth)acrylates, five- to seven-membered N-vinyl lactams,N,N-di-C₁-C₄alkyl(meth)-acrylamides and vinylically unsaturatedcarboxylic acids having a total of from 3 to 5 carbon atoms.

Examples of suitable hydrophilic vinyl comonomers include hydroxyethylmethacrylate, hydroxyethyl acrylate, acrylamide, methacrylamide,dimethylacrylamide, allyl alcohol, vinyl-pyridine, vinylpyrrolidine,glycerol methacrylate, N-(1,1-dimethyl-3-oxobutyl)-acrylamide and thelike.

Preferred hydrophobic vinyl comonomers are methyl methacrylate and vinylacetate. Preferred hydrophilic vinyl comonomers are 2-hydroxyethylmethacylate, N-vinylpyrrolidone and acrylamide. Most preferably, thecrosslinking of the copolymers of formula (1) is carried out in theabsence of a vinylic comonomer.

According to another preferred embodiment of the invention, thecopolymers of formula (1) are previously converted into a mesophasewhich is at least partly bicontinuous, and the mesophase is thensubjected to photocrosslinking. A suitable process producing a mesophasecomposition is disclosed in PCT patent application WO 99/12059, whichapplication is herein incorporated by reference.

The term mesophase in this context is to be understood as meaning athermodynamically stable mixture of an amphiphilic substance such as acrosslinkable block copolymer of formula (1) and an aqueous solution ora melt of an above-mentioned crosslinkable amphiphilic block copolymerwhich shows in each case a self-assembled microstructure. Mesophases aretypically homogeneous and optical transparent mixtures which lie insingle phase regions of the phase diagram of the components the systemis based on. These single phases may be of a liquid crystalline nature(such as lamellar, hexagonal or cubic) which indicates an orderedcompartmentisation of components in the mixture with a geometricallyregular and repeated structure, or may be of a non-crystalline nature inwhich compartmentisation is random and isotropic. An example for thislatter type of mesophases is represented by microemulsions. Accordingly,many microstructures can occur within the general class of mesophases.Within the present invention, mesophases having a liquid crystallinemicrostructure are preferred. The mesophases of the claimed process thuspreferably lie in single phase regions of the phase diagram that exhibita crystalline structure and most preferably a cubic structure.

In addition, the mesophases of this embodiment are at least partlybicontinuous, that is to say the mixture has at least two partlybicontinuous phases, for example an oxygen-permeable and anion-permeable phase, which are intermingled.

A “phase”, as used herein, refers to a region of substantially uniformcomposition which is a distinct and physically separate portion of aheterogeneous polymeric material. However, the term “phase” does notimply that the material described is a chemically pure substance, butmerely that certain bulk properties differ significantly from theproperties of another phase within the material. Thus, with respect tothe polymeric components of an ophthalmic molding such as a lens, anion-permeable phase refers to a region composed of essentially onlyion-permeable polymer (and water, when hydrated), while anoxygen-permeable phase refers to a region composed of essentially onlyoxygen-permeable polymer (and perhaps a small amount of water, whenhydrated).

“Bicontinuous phases”, as used herein, refers to at least two regions,each of substantially uniform composition which differs from the other,and each of which exhibiting its individual properties. With respect toophthalmic moldings such as contact lenses it has been found that it ishighly desirable to have bicontinuous phases of an oxygen-permeablepolymer and an ion-permeable polymer which provide the lens with twocontinuous pathways or sets of continuous pathways extending from theinner surface of the lens to the outer surface of the lens. Said atleast two continuous pathways ensure that the lens material has both ahigh oxygen transmissibility and ion or water permeability.

The mesophases may be prepared from a melt of one or more than onedifferent copolymers of formula (1) and optionally further componentsor, preferably, from (i) one or more than one different copolymers offormula (1), (ii) an aqueous solution and optionally (iii) furthercomponents.

(ii) Aqueous Solution;

The aqueous solution that is added to form the mesophase may be purewater or a mixture of water and one or more water-miscible solventsand/or salts.

(ii-a) Water-Miscible Organic Solvents;

Examples of suitable solvents that may be added to the mesophase are amonohydric or polyhydric alcohol, for example a C₁-C₈alcohol such asn-butanol, n-propanol, ethanol or methanol or a polyhydric alcohol suchas glycerol or a glycol; a polyether such as Butyl Cellosolve™, ButylCarbitol™, Hexyl Cellosolve™, or Hexyl Carbitol™; a carboxylic acidamide, for example N,N-dimethylformamide; acetone, acetonitrile;dimethyl sulfoxide; or mixtures thereof. Preferably, the aqueoussolution does not comprise any additional organic solvent or comprises aC₁-C₄alcohol, for example ethanol or methanol as additional organicsolvent. In a particularly preferred embodiment of the invention, theaqueous solution does not comprise an additional organic solvent.

(ii-b) Salts;

Salts that may be comprised in the aqueous solution used to form theinventive mesophases include without limitation thereto physiologicallytolerable salts, such as buffer salts customary in the field of contactlens care, for example phosphate salts, or isotonising agents customaryin the field of contact lens care, such as alkali halides, for examplesodium chloride, or mixtures thereof.

If salts are added, the aqueous salt solution has for example anosmolarity of from about 200 to 450 milliosmol in 1000 ml (unit:mOsm/l), preferably an osmolarity of from about 250 to 350 mOsm/l, andin particular about 300 mOsm/l.

An example of an especially suitable aqueous salt solution of theinvention is an artificial, preferably buffered, lacrimal fluid that inrespect of pH value and osmolarity is adapted to natural lacrimal fluid,for example, a sodium chloride solution that is unbuffered or that ispreferably buffered, for example, by a phosphate buffer, and that has anosmolarity that corresponds to the osmolarity of human lacrimal fluid.

The aqueous solution employed for the formation of the mesophases of theinvention is preferably a pure solution which means a solution which isfree or essentially free from undesired constituents. Especiallypreferred examples of such solutions are pure water or an artificiallacrimal fluid, as defined hereinbefore.

(iii) Optional Further Components;

Optional further components which are used for the preparation of themesophases, besides the crosslinkable block copolymer of formula (1) andthe aqueous solution, are for example: (iii-a) a photoinitiator, forexample one of the photoinitiators mentioned above; (iii-b) a surfactantwhich may be any conventional non-ionic, cationic or zwitterionicsurfactant known in the art; (iii-c) a hydrophobic or hydrophiliccomonomer wherein the above given meanings and preferences apply; or(iii-d) a pharmaceutical effective agent, for example a protein, enzyme,vitamin, disinfectant, bactericide or the like.

The mesophases of the present invention may be prepared by simplyadmixing suitable amounts of the copolymer of formula (1), the aqueoussolution and optionally further components in any order at a temperatureof, for example, 0 to 100° C., preferably 10 to 50° C., and morepreferably 15 to 40° C. The mesophases may form spontaneously or uponstirring and/or standing for a suitable period. For example, thecomponents that make up the mesophase are mixed for about 1 minute to 1week, preferably for 30 minutes to 5 days and most preferably 2 hours to3 days, in order to form a mesophase which is ready for being furtherprocessed according to the invention.

According to another embodiment of the invention, a mesophase may beobtained by simply preparing a melt of the copolymer and optionallyfurther components in the absence of an aqueous solution which isespecially suited for prepolymers having a low melting or glasstransition point.

The mesophases of the invention comprise, for example, from 10 to 100percent by weight of copolymer(s) of formula (1), from about 0 to about90 percent by weight of aqueous solution and from 0 to 40 percent byweight of further components. Preferably, the bicontinuous mesophases ofthe invention comprise from about 30 to about 85 percent by weight ofcopolymer(s) of formula (1), from about 15 to about 70 percent by weightof aqueous solution and from 0 to 10 percent by weight of furthercomponents. Particularly preferred mesophases comprise from 30 to 75percent by weight of copolymer(s) of formula (1) and from 25 to 70percent by weight of aqueous solution.

The solutions or mesophases comprising a block copolymer of formula (1)may be processed in a manner known per se to form moldings, especiallycontact lenses, for example by carrying out the photo-crosslinking ofthe copolymers of the invention in a suitable mold, in particular acontact lens mold. For example, the solution or mesophase is introducedinto an opthalmic mold in a manner known per se, such as, especially, byconventional metering in, for example by dropwise introduction or byextrusion. Suitable molds are generally customary contact lens molds asknown in the state of the art. Thus, the contact lenses according to theinvention can be manufactured, for example, in a manner known per se,for example in a conventional “spin-casting mold”, as described, forexample, in U.S. Pat. No. 3,408,429, or by the so-called Full-Mouldprocess in a static mold, as described, for example, in U.S. Pat. No.4,347,198. Appropriate molds are made, for example, from polypropylene.Quartz, sapphire glass and metals, for example, are suitable materialsfor re-usable molds.

The crosslinking can be triggered in the mold, for example by actinicradiation, such as, for example, UV light, or by ionising radiation,such as, for example, gamma radiation, electron radiation or Xradiation. The crosslinking can where appropriate also be triggeredthermally or electrochemically. Attention is drawn to the fact that thephotocrosslinking can be carried out in a very short time, for examplein ≦60 minutes, preferably ≦20 minutes, more preferably ≦5 minutes evenmore preferably in ≦1 minute, especially in up to 30 seconds, especiallypreferably, as disclosed in the examples.

The opening of the mold such that the molding can be removed from themold can be carried out in a manner known per se.

The moldings obtainable from the block copolymers of formula (1) arepreferably at least partly bicontinuous, that is to say the moldings, asstated before, have at least two partly bicontinuous phases, for examplean oxygen-permeable and an ion-permeable phase, which are intermingled.

The invention further relates, therefore, to moldings that comprise or,preferably, substantially consist of a crosslinked block copolymer offormula (1). Further examples of moldings of the invention, apart fromcontact lenses, are biomedical or special ophthalmic moldings, e.g.intraocular lenses, artificial cornea, eye dressings, moldings for usein surgery, such as heart valves, artificial arteries or the like, andfilms or membranes, e.g. membranes for controlling diffusion,photo-structurable films for information storage, or photoresistmaterials, e.g. membranes or moldings for etch resists or screen printresists.

If the molding manufactured according to the invention is a contact lensand the latter has been manufactured under solventless conditions from apreviously purified prepolymer of the invention, then it is normallyunnecessary for the removal of the molding to be followed bypurification steps, e.g. extraction, because the prepolymers used do notcontain any undesired low-molecular-weight constituents; consequently,the crosslinked product also is free or substantially free of suchconstituents and subsequent extraction can be dispensed with. Thecontact lens can accordingly be converted into a ready-for-use contactlens directly in conventional manner by hydration. Suitable forms ofhydration capable of producing ready-for-use contact lenses with a widevariety of water contents are known to the person skilled in the art.The contact lens is swelled, for example, in water, in an aqueous saltsolution, especially in an aqueous salt solution having an osmolarity ofapproximately from 200 to 450 milliosmol in 1000 ml (unit: mosm/l),preferably approximately from 250 to 350 mosm/l and especiallyapproximately 300 mosm/l, or in a mixture of water or an aqueous saltsolution with a physiologically tolerable polar organic solvent, forexample glycerol. Swelling of the prepolymer in water or in aqueous saltsolutions is preferred.

The aqueous salt solutions used for the hydration are advantageouslysolutions of physiologically tolerable salts, such as buffer saltscustomary in the field of contact lens care, e.g. phosphate salts, orisotonising agents customary in the field of contact lens care, such as,especially, alkali metal halides, e.g. sodium chloride, or solutions ofmixtures thereof. An example of an especially suitable salt solution isa synthetic, preferably buffered, lachrymal fluid that has been matchedto natural lachrymal fluid with regard to pH value and osmolarity, e.g.an unbuffered or preferably buffered, for example phosphatebuffer-buffered, sodium chloride solution the osmolarity and pH value ofwhich correspond to the osmolarity and pH value of human lachrymalfluid.

The hydration fluids defined above are preferably pure, that is to sayfree or substantially free of undesired constituents. Most preferably,the hydration fluid is pure water or a synthetic lachrymal fluid asdescribed above.

If the molding manufactured according to the invention is a contact lensand the latter has been manufactured from an aqueous mesophase of apreviously purified copolymer of the invention, the crosslinked productalso will not contain any troublesome impurities. There is normally noneed, therefore, for subsequent extraction. Since the crosslinking iscarried out in an aqueous medium, there is also no need for subsequenthydration. In accordance with an advantageous embodiment, therefore, thecontact lenses obtainable by this process are distinguished by the factthat they are suitable for use as intended without extraction orhydration. The expression “use as intended” is understood in thiscontext to mean especially that the contact lenses can be inserted intothe human eye.

The copolymers of the invention are especially suitable for themanufacture of mass-produced articles, such as, for example, contactlenses that are worn for a short time, for example for a month, a weekor just one day, and are then replaced by new lenses. This is inparticular because contact lenses prepared from a mesophase of thecopolymers can be used for their intended use without subsequenttreatment steps, such as extraction or hydration. The copolymers of theinvention are further useful for the manufacture of biomedical devicesof all kinds, for example ophthalmic moldings such as intraocular lensesor artificial cornea, wound healing dressings, eye bandages, materialsfor the sustained release of an active compound such as a drug deliverypatch, moldings that can be used in surgery, such as heart valves,vascular grafts, catheters, artificial organs, encapsulated biologicimplants, e.g. pancreatic islets, materials for prostheses such as bonesubstitutes, or moldings for diagnostics, membranes or biomedicalinstruments or apparatus.

In addition, biomedical devices, for example ophthalmic moldings such asin particular contact lenses obtainable according to the invention havea range of unusual and extremely advantageous properties and aretherefore suited to extended periods of wear (true extended wear, i.e.,seven days or more). Among these properties are, for example, theirexcellent compatibility with the human cornea and with tear fluid, whichis based on a balanced ratio between water content, oxygen permeability,ion permeability and mechanical and absorptive properties.

In particular, moldings obtainable from a block copolymer of theinvention do have a high surface wettability which can be demonstratedby their contact angles, their water retention and their water-filmbreak up time or tear film break up time (TBUT).

The TBUT plays an particularly important role in the field of ophthalmicdevices such as contact lenses. Thus the facile movement of an eyelidover a contact lens has proven important for the comfort of the wearer;this sliding motion is facilitated by the presence of a continuous layerof tear fluid on the contact lens, a layer which lubricates thetissue/lens interface. An increased wettability of the surfacefurthermore contributes substantially to low microbial adhesion andresistance to deposit formation.

The above outlined properties of the novel copolymers impart a highcomfort and the absence of irritation and allergenic effects tobiomedical moldings derived therefrom. Owing to their favourablepermeability properties with respect to gases (CO₂ and O₂), varioussalts, nutrients, water and diverse other components of tear fluid, thecontact lenses prepared according to the process of the invention haveno effect, or virtually no effect, on the natural metabolic processes inthe cornea. Furthermore, the contact lenses obtainable according to theprocess are optical clear and transparent, have a high shelf life andgood mechanical properties, for example concerning the modulus ofelasticity, elongation at break or dimensional stability.

All of the advantages mentioned above, in particular those concerningthe surface wettability, apply to moldings derived from an amphiphilicblock copolymer of the invention per se, that is to say without anysubsequent surface treatment, e.g. coating. The block copolymers of theinvention thus may be processed directly to biomedical moldings, inparticular ophthalmic moldings, without any subsequent surfacetreatment, e.g. coating, whereas known polymeric materials in generalhave to be coated with an hydrophilic coating in order to be useful as abiomedical molding that comes in direct contact with the human body.

The above-mentioned advantages apply, of course, not only to ophthalmicmoldings such as contact lenses but also to other moldings of theinvention. The sum of the various advantageous aspects in themanufacture of the moldings of the invention results in the moldings ofthe invention being especially suitable as mass-produced articles, suchas, for example, contact lenses that are worn for a short period andthen replaced by new lenses.

In the Examples which follow, amounts are by weight, unless specifiedotherwise, and temperatures are given in degrees Celsius. Dynamiccontact angle measurements are obtained using the dynamic Wilhelmy platemethod, that is the wetting force on the solid is measured as the solidis immersed in or withdrawn from a liquid of known surface tension.

EXAMPLE 1

a) 11.8 g (15.5 mmol) poly(ethyleneglycol) mono-methyl ether, M_(n) 750(PEG750) are dissolved in 13.8 g anhydrous dichloroethane (DCE) in around-bottomed flask. The PEG750 is dried by refluxing the water/DCEazeotrope through molecular sieves in a Soxhlet funnel. After drying,the contents of the flask is cooled, and 10.2 g (45.8 mmol)isophoronediisocyante (IPDI) are then added to the flask, along with 100mg dibutyltin dilaurate (DBTDL). The contents are mixed overnight atroom temperature. The solution is poured into a separatory funnel andthe excess IPDI extracted with anhydrous hexane. The waxy-liquidPEG(750)-IPDI product is drained into a RBF and solvent removed undervacuum. The product is stored under vacuum over a weekend, then undernitrogen.

(b) In a three-necked round-bottomed flask are dissolved 8.0 g (1.4mmol) of the compound of formula

wherein Q* is a radical —O—C(O)—NH—(CH₂)₂—O—C(O)—C(CH₃)═CH₂ (synthesissee PCT application WO 96/36890) in 30 g anhydrous dichloroethane. Tothis solution are added 4.1 g (4.1 mmol) of the PEG(750)-IPDI. The flaskis equipped with a condenser, a thermometer, stir bar, and heatingmantle. The mixture is stirred and heated to 45° C. DBTDL catalyst isadded, and dry air is infused through the system. After 7 days, noisocyanate peak is visible in the IR, and the solution is then cooled.The solvent is removed via rotary evaporation to yield 10.2 g of aproduct corresponding to the above formula (15), wherein 3 hydroxygroups have been substituted by a radical of formula

c) 0.8109 g of the product obtained according to step b) are mixed with0.2 g water containing 0.01% of a photoinitiator (Darocur® 2959). Thismixture is centrifuged, refrigerated overnight, mixed, and recentrifugeduntil the formulation looks homogeneous and transparent. Thisformulation is cast on quartz plates that had been soaked overnight inKOH/isopropanol, rinsed with ethanol, then rinsed with purified waterand air dried. The films are cured for 90 seconds under a UV lamp, andextracted with an isopropanol/water mixture. Dynamic contact anglemeasurements are obtained which indicate a high surface wettability ofthe films.

EXAMPLE 2

a) 15.0 g (7.8 mol) poly(ethyleneglycol) mono-methyl ether, M_(n) 1900(PEG1900) is dissolved in 20 g anhydrous dichloromethane in around-bottomed flask. The PEG1900 is dried by refluxing thewater/dichloromethane azeotrope through molecular sieves in a Soxhletfunnel. After drying, the contents of the flask are cooled, and 5.3 g(24.0 mmol) isophoronediisocyante (IPDI) are added to the flask, alongwith 100 mg dibutyltin dilaurate (DBTDL). The contents are mixed overthe weekend at room temperature. The solution is poured into aseparatory funnel and the excess IPDI extracted with anhydrous hexane.The PEG-IPDI product is drained into a RBF and solvent removed undervacuum. The product is stored under vacuum.

b) In a round-bottomed flask are dissolved 5.03 g (0.13 mmol) of acompound of formula

in 10.4 g anhydrous dichloroethane (DCE). To this solution are added 1.9g (1.9 mmol) of the PEG(1900)-IPDI product according to step a)dissolved in 10.2 g anhydrous DCE. The mixture is stirred at roomtemperature under nitrogen for 3.5 hours. Then 0.26 g (1.7 mmol) ofisocyanatoethyl methacrylate are added to the mixture, which is stirredunder infused dry air a few hours, until the isocyanate peak is nolonger visible in the IR. The solvent is then removed via rotaryevaporation to yield a product of the above formula (17), wherein about35% of the amino groups are substituted by a radical of formula

and the remaining amino groups are substituted by a radical—O—C(O)—NH—(CH₂)₂—O—C(O)—C(CH₃)═CH₂.

c) 1.51 g of the product obtained according to step b) are mixed with1.51 g ethanol and 7.5 mg of a photoinitiator (Darocur® 1173). Thismixture is stirred to dissolve, degassed, and cast in a dry box onquartz plates that has been soaked overnight in KOH/isopropanol, rinsedwith ethanol, then rinsed with purified water and air dried. The flatsare cured for 15 minutes under a UV lamp, and extracted with anisopropanol/water mixture. Dynamic contact angle measurements areobtained which indicate a high surface wettability of the flats.

EXAMPLE 3

(a) 11.8 g (15.5 mmol) poly(ethyleneglycol) mono-methyl ether (PEG750)are dissolved in 13.8 g anhydrous dichloroethane (DCE) in around-bottomed flask. The PEG750 is dried by refluxing the water/DCEazeotrope through molecular sieves in a Soxhlet funnel. After drying,the contents of the flask are cooled, and 10.2 g (45.8 mmol)isophoronediisocyanate (IPDI) are added to the flask, along with 100 mgdibutyltin dilaurate (DBTDL). The contents are mixed overnight at roomtemperature. The solution is poured into a separatory funnel and theexcess IPDI extracted with anhydrous hexane. The waxy-liquidPEG(750)-IPDI product is drained into a RBF and solvent removed undervacuum. The product is stored under vacuum over a weekend, then undernitrogen.

b) To a three-necked round-bottomed flask are added 0.87 g (4.88 mmol)D(+) gluconic acid-δ-lactone, and 21 ml anhydrous tetrahydrofuran. Theflask is equipped with a condenser, a thermometer, stir bar, and heatingmantle. An addition funnel containing 10.00 g (0.26 mmol) of thecompound of formula (17) according to Example 2 is also attached, anddry nitrogen is infused through the system. The contents of the flaskare heated to 38° C. The solution of the compound of formula (17) isadded dropwise to the stirring gluconolactone solution. The reaction isstirred at 38° C. overnight. The mixture is then cooled and stirred atroom temperature over the weekend. The solvent is removed under vacuum.There are obtained 10.59 g of a product according to formula (17)wherein the amino groups are each substituted by a radical of formula—NH—C(O)—CH(OH)—CH(OH)—CH(OH)—CH(OH)—CH₂—OH.

c) 4.00 g (0.094 mmol) of the product obtained according to step (b) areweighted into a three-necked round-bottomed flask, along with 25.59 gtetrahydrofuran. Next, 1.30 g (1.32 mmol) PEG(750)-IPDI obtainedaccording to step a) and 0.07 g (0.45 mmol) isocyanatoethyl methacrylateare added to the flask, and the mixture stirred. The flask is placedatop a stir plate and equipped with heating mantle, condenser, andthermometer. Dry air is infused throughout the system. The reactants arebrought to 41° C., and 100 mg dibutyltin dilaurate are added to thereaction mixture. The mixture is stirred at 41° C. over the weekend. Themixture is then cooled and the solvent removed under reduced pressure.5.30 g of a clear, crystalline compound corresponding to formula (17)wherein the amino groups are each substituted by a radical of formula—NH—C(O)—CH(OH)—CH(OH)—CH(OH)—CH(OH)—CH₂—OH and about 13% of the hydroxygroups are substituted by a radical of formula

and about 4% of the hydroxy groups are substituted by a radical offormula

are recovered.

d) 1.1 g of the product obtained according to step c) are mixed with 1.1g ethanol and 9.4 mg of a photoinitiator (Darocur® 1173). Thisformulation is cast on quartz plates that have been soaked overnight inKOH/isopropanol, rinsed with ethanol, then rinsed with purified waterand air dried. The films are cured for 90 seconds under a UV lamp, andextracted with an isopropanol/water mixture. Dynamic contact anglemeasurements are obtained which indicate a high wettability of the filmsobtained.

EXAMPLE 4

A 50 ml addition funnel containing 1.0 g of the compound of formula

(M_(w)˜1500, synthesis from HO—(CH₂CH₂N[C(O)CH₃])_(p)—CH₂—C₆H₅—CH═CH₂)prepared according to S. Kobayashi et al., Polymer Bulletin 13, p447-451 (1985) and isophorone diisocyanate) and 1.0 g of the compound offormula

(M_(w)˜1300, synthesis from isophorone diisocyanate andHO—(CH₂CH₂N[C(O)CH₃])_(p)—CH₃ in 10.1 g dry methylene chloride is placedatop a 100 ml round-bottomed flask, equipped with a stir bar andcontaining 3.0 g of the distilled compound of formula

M_(w) about 10000, and 10.2 g dry methylene chloride. The flask isplaced atop a stir plate, and a septum placed in the add-funnel neck.Stirring is started and addition of the polymethyl oxazoline materialsstarts. The addition takes 40 minutes, after which the mixture isstirred an additional 4 hours at room temperature. One drop of DBTDL isadded to the reaction mixture, which is stirred an additional hour. Thesolvent is then removed via rotary evaporation.

The macromer obtained above is formulated 68.62% in water containing0.5% of a photoinitiator (Irgacure® 2959). It is centrifuged andstirred. The formulation is cast on quartz plates, and cured for 60seconds. Thereafter the flats are pealed off the quartz plates, placedin water and autoclaved. Dynamic contact angle measurements are obtainedwhich indicate a high wettability of the films obtained.

COMPARATIVE EXAMPLE

The manufacture of the molding above is repeated but using 2 g of thecompound of formula (18a) instead of the mixture of 1 g each of acompound of formula (18a) and (18b). Dynamic contact angle measurementsare obtained which indicate a considerable decrease in wettabilitycompared to the molding obtained with the mixture of compounds (18a) and(18b).

1. An amphiphilic block copolymer of formula (1)

wherein A is a hydrophobic polysiloxane or perfluoroalkyl polyethersegment; B is a surface-modifying hydrophilic segment having a weightaverage molecular weight of ≧100 that is devoid of a crosslinkablegroup, wherein (a) B is a non-ionic segment selected from the groupconsisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacrylamide, polyvinyl alcohol, polyvinyl ether and apolyol; or (b) B is a polyionic segment selected from the groupconsisting of a polyallylammonium, polyethyleneimine,polyvinylbenzyltrimethylammonium, polyaniline, sulfonated polyaniline,polypyrrole, polypyridinium segment, a polyacrylic, polymethacrylicacid, a polythiophene-acetic acid, a polystyrenesulfonic acid, azwitterionic segment, and a salt thereof; Q is a moiety comprising atleast one crosslinkable ethylenically unsaturated group; (alk) isC₂-C₂₀-alkylene which is unsubstituted or substituted by hydroxy; L₁, L₂and L₃ are each independently of the other a linking group; p1 and q1are each independently of the other an integer from 1 to 12; and eithert is 0 and p and q are each independently of the other an integer from 1to 25; or t is an integer from 1 to 8 and p and q are each
 0. 2. Theamphiphilic block copolymer of claim 1, wherein t is the number 2, p andq is the number zero, wherein the amphiphilic block copolymer is definedby formula (1a)

wherein A, B, L₁, L₂, L₃, Q, (alk), p1 and q1 are each as defined inclaim
 1. 3. The amphiphilic block copolymer of claim 1, wherein t is thenumber zero, wherein the amphiphilic block copolymer is defined byformula (1b)

wherein A, B, L₁, L₂ and Q are each as defined in claim 1, and p and qare each independently of the other an integer from 2 to
 20. 4. Theamphiphilic block copolymer of claim 1, wherein A is a polysiloxanesegment of formula

wherein (alk′) is alkylene having 1 to 20 carbon atoms which may beinterrupted by —O—; x is 0 or 1; 80 to 100% of the radicals R₁, R₁′,R₁″, R₂, R₂′, R₂″, R₃ and R₄, independently of one another, areC₁-C₈-alkyl, and 0-20% of the radicals R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃and R₄, independently of one another, are unsubstituted or C₁-C₄ alkyl-or C₁-C₄-alkoxy-substituted phenyl, fluoro(C₁-C₁₈-alkyl) orcyano(C₁-C₁₂-alkyl), s₁ is an integer from 5 to 700; s₂ is the sum of(p+q+t−2) if x is 0, and is the sum of (p+q+t) if x is 1; wherein p, qand t are as defined in claim 1, and the sum (s₁+s₂) is from 5 to 700.5. The amphiphilic block copolymer of claim 1, wherein L₁, L₂ and L₃ areeach independently of the other a bivalent linking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e), wherein X₁ and X₂ are each independently of theother a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀is linear or branched C₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl-or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene.
 6. The amphiphilicblock copolymer of claim 5, wherein L₁ is a linking group of formula(4a), (4c) or (4e), L₂ is a linking group of formula (4a), and L₃ is alinking group of formula (4b) or (4c).
 7. The amphiphilic blockcopolymer of claim 1, wherein B is a non-ionic segment selected from thegroup consisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacryl amide, polyvinyl alcohol, polyvinyl ether anda polyol.
 8. The amphiphilic block copolymer of claim 1, wherein Q is aradical Q₁ of formula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or
 1. 9.The amphiphilic block copolymer of claim 1, wherein Q is apolyoxyalkylene, poly(vinylpyrrolidone), poly(hydroxyethylacrylate),poly(hydroxyethylmethacrylate), polyacrylamide,poly(N,N-dimethylacrylamide), polyacrylic acid, polymethacrylic acid,polyacyl alkylene imine or a copolymeric mixture of two or more of theabove-mentioned polymers which in each case comprises one or moreethylenically unsaturated bond and has a weight average molecular weightof ≧100.
 10. The amphiphilic block copolymer of claim 9, wherein Q is ahydrophilic segment of formula

wherein L₁′ is a bivalent linking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e), wherein X₁ and X₂ are each independently of theother a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀is linear or branched C₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl-or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene, Q₂ is a radical offormula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or 1, Q3is C₃-C₁₂-alkenyl or a radical —(CH₂)₁₋₄—O—R₁₆ wherein R₁₆ is acryloyl,methacryloyl or a group —C(O)—NH—(CH₂)₂₋₄—O—C(O)—C(R₁₇)═CH₂ and R₁₇ ishydrogen or methyl, Q4 is a radical of formula

wherein X₃ is —O— or —NR, R is hydrogen or C₁-C₄-alkyl, X₄ is a group—C(O)—O—, —O—C(O)—NH— or —NH—C(O)—O—, (Alk′) is C₁-C₈-alkylene, e is aninteger of 0 or 1, and R₁₈ is C₁-C₁₂-alkylene, phenylene orC₇-C₁₂-phenylenealkylene, one of the radicals R₆ and R₇ is hydrogen andthe other is methyl, (alk″) is C₁-C₆-alkylene, c is the number 0 or 1,and each of a and b independently of the other is a number from 0 to100, the sum of (a+b) being from 2 to 100, R₈ is hydrogen; C₁-C₁₂-alkylunsubstituted or substituted by hydroxy or fluoro and/or uninterruptedor interrupted by oxygen; C₅-C₈-cycloalkyl; phenyl; or benzyl, R₉ isC₁-C₁₂-alkyl, benzyl, C₂-C₄-alkanoyl, benzoyl or phenyl, and z is aninteger from 2 to
 150. 11. The amphiphilic block copolymer of claim 1,wherein A is a polysiloxane segment of formula

wherein x and s₂ are each 0, and R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄are each independently of one another C₁-C₄-alkyl, L₁ is a linking groupof formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—  (4c), or—X₁—C(O)—X₂—  (4e), L₂ is a linking group of the above formula (4a), andL₃ is a linking group of the above formula (4c) or of the formula—X₁—C(O)—R₁₀—C(O)—X₂—  (4b), wherein X₁ and X₂ are each independently ofthe other a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, andR₁₀ is linear or branched C₁-C₁₈-alkylene or unsubstituted orC₁-C₄-alkyl- or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene,C₇-C₁₈-aralkylene, C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene,C₃-C₈-cycloalkylene, C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene, Q is a radical Q₁ offormula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or 1, orQ is a polyoxyalkylene, poly(vinylpyrrolidone),poly(hydroxyethylacrylate), poly(hydroxyethylmethacrylate),polyacrylamide, poly(N,N-dimethylacrylamide), polyacrylic acid,polymethacrylic acid, polyacyl alkylene imine or a copolymeric mixtureof two or more of the above-mentioned polymers which in each casecomprises one or more ethylenically unsaturated bond and has a weightaverage molecular weight of ≧100, and p1 is an integer from 1 to 6, andq1 is an integer from 1 to 8, B is a non-ionic segment selected from thegroup consisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacryl amide, polyvinyl alcohol, polyvinyl ether anda polyol, or B is a polyionic segment selected from the group consistingof polyallylammonium, polyethyleneimine,polyvinylbenzyltrimethylammonium, polyaniline, sulfonated polyaniline,polypyrrole, polypyridinium segment, polyacrylic acid, polymethacrylicacid, polythiophene-acetic acid, polystyrenesulfonic acid, azwitterionic segment, and a salt thereof.
 12. The amphiphilic blockcopolymer of claim 2, wherein A is a polysiloxane segment of formula

wherein x and s₂ are each 0, and R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄are each independently of one another C₁-C₄-alkyl, L₁ is a linking groupof formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—  (4c), or—X₁—C(O)—X₂—  (4e), L₂ is a linking group of the above formula (4a), andL₃ is a linking group of the above formula (4c) or of the formula—X₁—C(O)—R₁₀—C(O)—X₂—  (4b), wherein X₁ and X₂ are each independently ofthe other a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, andR₁₀ is linear or branched C₁-C₁₈-alkylene or unsubstituted orC₁-C₄-alkyl- or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene,C₇-C₁₈-aralkylene, C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene,C₃-C₈-cycloalkylene, C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene, Q is a radical Q₁ offormula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or 1, orQ is a polyoxyalkylene, poly(vinylpyrrolidone),poly(hydroxyethyl-acrylate), poly(hydroxyethylmethacrylate),polyacrylamide, poly(N,N-dimethylacrylamide), polyacrylic acid,polymethacrylic acid, polyacyl alkylene imine or a copolymeric mixtureof two or more of the above-mentioned polymers which in each casecomprises one or more ethylenically unsaturated bond and has a weightaverage molecular weight of ≧100, and p1 is an integer from 1 to 6, andq1 is an integer from 1 to 8, B is a non-ionic segment selected from thegroup consisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacryl amide, polyvinyl alcohol, polyvinyl ether anda polyol, or B is a polyionic segment selected from the group consistingof polyallylammonium, polyethyleneimine,polyvinylbenzyltrimethylammonium, polyaniline, sulfonated polyaniline,polypyrrole, polypyridinium segment, polyacrylic acid, polymethacrylicacid, polythiophene-acetic acid, polystyrenesulfonic acid, azwitterionic segment, and a salt thereof.
 13. The amphiphilic blockcopolymer of claim 3, wherein p and q are each independently of theother an integer 2 to 15, A is a polysiloxane segment of formula

wherein x and s₂ are each 0, and R₁, R₁′, R₁″, R₂, R₂′, R₂″, R₃ and R₄are each independently of one another C₁-C₄-alkyl, L₁ is a linking groupof formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—  (4c), or—X₁—C(O)—X₂—  (4e), L₂ is a linking group of the above formula (4a), andL₃ is a linking group of the above formula (4c) or of the formula—X₁—C(O)—R₁₀—C(O)—X₂—  (4b), wherein X₁ and X₂ are each independently ofthe other a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, andR₁₀ is linear or branched C₁-C₁₈-alkylene or unsubstituted orC₁-C₄-alkyl- or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene,C₇-C₁₈-aralkylene, C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene,C₃-C₈-cycloalkylene, C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene, Q is a radical Q₁ offormula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or 1, orQ is a polyoxyalkylene, poly(vinylpyrrolidone),poly(hydroxyethyl-acrylate), poly(hydroxyethylmethacrylate),polyacrylamide, poly(N,N-dimethylacrylamide), polyacrylic acid,polymethacrylic acid, polyacyl alkylene imine or a copolymeric mixtureof two or more of the above-mentioned polymers which in each casecomprises one or more ethylenically unsaturated bond and has a weightaverage molecular weight of ≧100, and p1 is an integer from 1 to 6, andq1 is an integer from 1 to 8, B is a non-ionic segment selected from thegroup consisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacryl amide, polyvinyl alcohol, polyvinyl ether anda polyol, or B is a polyionic segment selected from the group consistingof polyallylammonium, polyethyleneimine,polyvinylbenzyltrimethylammonium, polyaniline, sulfonated polyaniline,polypyrrole, polypyridinium segment, polyacrylic acid, polymethacrylicacid, polythiophene-acetic acid, polystyrenesulfonic acid, azwitterionic segment, and a salt thereof.
 14. The amphiphilic blockcopolymer of claim 2, wherein L₁, L₂ and L₃ are each independently ofthe other a bivalent linking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e), wherein X₁ and X₂ are each independently of theother a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀is linear or branched C₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl-or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₈-alkylene-C₃-C₈-cycloalkylene-C₁-C₈-alkylene.
 15. The amphiphilicblock copolymer of claim 14, wherein L₁ is a linking group of formula(4a), (4c) or (4e), L₂ is a linking group of formula (4a), and L₃ is alinking group of formula (4b) or (4c).
 16. The amphiphilic blockcopolymer of claim 2, wherein B is a non-ionic segment selected from thegroup consisting of polysaccharide, polypeptide, poly(vinylpyrrolidone),polyhydroxyalkylacrylate, polyhydroxyalkylmethacrylate, polyacylalkylene imine, polyacryl amide, polyvinyl alcohol, polyvinyl ether anda polyol.
 17. The amphiphilic block copolymer of claim 2, wherein Q is aradical Q₁ of formula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or
 1. 18.The amphiphilic block copolymer of claim 2, wherein Q is apolyoxyalkylene, poly(vinylpyrrolidone), poly(hydroxyethylacrylate),poly(hydroxyethylmethacrylate), polyacrylamide,poly(N,N-dimethylacrylamide), polyacrylic acid, polymethacrylic acid,polyacyl alkylene imine or a copolymeric mixture of two or more of theabove-mentioned polymers which in each case comprises one or moreethylenically unsaturated bond and has a weight average molecular weightof ≧100.
 19. The amphiphilic block copolymer of claim 18, wherein Q is ahydrophilic segment of formula

wherein L₁′ is a bivalent linking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e), wherein X₁ and X₂ are each independently of theother a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀is linear or branched C₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl-or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene, Q₂ is a radical offormula

wherein (Alk) is linear or branched C₁-C₁₂-alkylene, X is —O— or —NH—,R₁₁ is an olefinically unsaturated copolymerizable radical having from 2to 24 carbon atoms which is unsubstituted or further substituted byC₁-C₄alkoxy, halogen, phenyl or carboxy, and w is the number 0 or 1, Q₃is C₃-C₁₂-alkenyl or a radical —(CH₂)₁₋₄—O—R₁₆ wherein R₁₆ is acryloyl,methacryloyl or a group —C(O)—NH—(CH₂)₂₋₄—O—C(O)—C(R₁₇)═CH₂ and R₁₇ ishydrogen or methyl, Q₄ is a radical of formula

wherein X₃ is —O— or —NR, R is hydrogen or C₁-C₄-alkyl, X₄ is a group—C(O)—O—, —O—C(O)—NH— or —NH—C(O)—O—, (Alk′) is C₁-C₈-alkylene, e is aninteger of 0 or 1, and R₁₈ is C₁-C₁₂-alkylene, phenylene orC₇-C₁₂-phenylenealkylene, one of the radicals R₆ and R₇ is hydrogen andthe other is methyl, (alk″) is C₁-C₆-alkylene, c is the number 0 or 1,and each of a and b independently of the other is a number from 0 to100, the sum of (a+b) being from 2 to 100, R₈ is hydrogen; C₁-C₁₂-alkylunsubstituted or substituted by hydroxy or fluoro and/or uninterruptedor interrupted by oxygen; C₅-C₈-cycloalkyl; phenyl; or benzyl, R₉ isC₁-C₁₂-alkyl, benzyl, C₂-C₄-alkanoyl, benzoyl or phenyl, and z is aninteger from 2 to
 150. 20. The amphiphilic block copolymer of claim 3,wherein L₁, L₂ and L₃ are each independently of the other a bivalentlinking group of formula—X₁—C(O)—NH—R₁₀—NH—C(O)—X₂—  (4a),—X₁—C(O)—R₁₀—C(O)—X₂—  (4b),—X₁—C(O)—  (4c),—C(O)—X₂—  (4d), or—X₁—C(O)—X₂—  (4e), wherein X₁ and X₂ are each independently of theother a group —O—, —S— or —NR₀—, R₀ is hydrogen or C₁-C₄-alkyl, and R₁₀is linear or branched C₁-C₁₈-alkylene or unsubstituted or C₁-C₄-alkyl-or C₁-C₄-alkoxy-substituted C₆-C₁₀-arylene, C₇-C₁₈-aralkylene,C₆-C₁₀-arylene-C₁-C₂-alkylene-C₆-C₁₀-arylene, C₃-C₈-cycloalkylene,C₃-C₈-cycloalkylene-C₁-C₆-alkylene,C₃-C₈-cycloalkylene-C₁-C₂-alkylene-C₃-C₈-cycloalkylene orC₁-C₆-alkylene-C₃-C₈-cycloalkylene-C₁-C₆-alkylene.